Boring tool



May 3, 1932- 1 G. w. MITCHELL ET AL BOR ING TOOL Filed May 27, 1930 INVEN TORS L 1 1 9.5.? a A WWW 1 MMM a 8? o 3 7 o 1 4 a Z%% A TTORNEY.

Patented May 3, 1932 UNITED STATES PATENT OFFICE 1 GEORGE W. MITCHELL,OF NORWALK, AND GAROLD 0. SHISLER, OF EAST SAN GABRIEL,

AND EDWARD E. MYERS, OF BELVEDERE GARDENS, CALIFORNIA BORING TOOLApplication filed May 27,

This invention relates to improvements in boring tools.

The general object of this invention is to provide an improved rotaryboring tool. Another object of the'invention is-to provide an improvedboring tool including a plura-lity of reamer rolls.

An additional object of this invention is to provide a novel reamer.

A further object of the invention is to provide a device of the classdescribed including a novel means for expanding the reamer rolls.

Other objects and the advantages of this invention will be apparent fromthe follow- 15 ing description taken in connection with the accompanyingdrawings wherein:

Fig. 1 is a central longitudinal section through our improved boringtool showing the reamer rolls in a retracted position.

Fig. 2 is a similar view showing the reamer rolls in an extendedposition. 7 N Fig. 3 is a bottom plan view of the device.

Fig. 4 is a section taken on line 44 of Fig. '2. f v 25 Fig. 5 is asection taken on line 5-5 of Fig.2. 7

Fig. 6 is a section taken on line 66 of Fig. 1, and

F-Fig. 7 is a section taken on line 77 of Referring to, the drawings byreference characters we have indicated our improved boring toolgenerallyat'lO. 'As shown the device 10comprises a body portion 12having a reduced externally threaded hub 13 at its upper end while atthe lower end it is shown as formed into a flat bit 14 having taperedsides 15 which converge to a point.

' Within the body 12 a coaxial recess or cham- 40 ber 16 is provided atthe bottom of which a "reduced recess 17 is provided from which 7apertures 18 extend outwardly to points adjacent the sides of'the bit14.

. In the outer face of the body 12 adjacent 45 the bottom of the chamber16 weprovide a plurality of recesses 1.9and in .the sides of the body weprovide a plurality of apertures 20 which registerwith the recesses 19and are preferably arranged. at an angle to the perpendicular with thelower end in advance in 1930. Serial No. 456,002.

B5 of which are adapted to engage the threads of the hub 13. The cap isprovided with a reduced coaxial bore 23 and between the threaded recess22 and the reduced bore 23 an enlarged chamber 24 is provided.Intermediate the length of the bore 23 we provide arcuate coaxialrecesses 25 which terminate at one end in shoulders 26 and at theopposite end communicate with longitudinal slots 27 (see Fig. 4). At theshoulder end of each of the coaxial recesses 25 a downwardly extendingseat 25 is provided and at the slot end of each of the recesses 25 anupwardly extending seat 25 is provided.

Positioned in each of the recesses 19 of the body 12 we provide a block28 which is adapted to be secured in position by a pin 29 positi oned inapertures 30 provided in the body. In the upper face of each of theblocks we provide a recess 31 in which the lower end of a shaft 32 ispositioned. The upper ends of the shafts 32 are positioned in blocks 33which are positioned in the apertures 20 and each of the blocks 33include an upwardly extending cam engaging tongue 34 which is providedin the chamber 16 and extends upwardly above the top of the aperture 20.Intermediate the length of the shafts 32 other blocks 35 are providedthrough which the shafts extend and which are positioned in theapertures 20 and which include enlarged cam engaging inner portions 36.

V Mounted to rotate on the shafts 32 intermediate the lower blocks 28and the center blocks 35 we provide a reamer roller 37 which may be asingle roller or made up of a plurality' of sections as shown. Similarlymounted on the shafts 32 intermediate the center block 35 and the upperblock 33 we provide reamer rolls 38.

For actuating the reamers to operative position we provide a stem 40which is positioned in the bore 23 of the cap and includes at its upperend a reduced externally threaded hub 41 by means of which it is adapted10c to be secured to a string of drill pipe. Intermediate the length ofthe stem 40 we provide an enlarged collar 42 which may be made integraltherewith or secured thereto by welding or in any desired manner. Thecollar 42 is positioned in the chamber 24 and is of less height than thechamber to allow the stem to move longitudinally the distance of thedepth of the seat portions and 25 in the recesses 25. p e

' Adjacent the lower end of the stem 23 we provide a reduced portion 43which includes tion thereof with a coaxialfbore 48." which communicateswith a co'axial'reduced bore 49 which extends through the bottom "of thestem and opens into' the chamber 16 and communicating withthe-reduced'bore 49 we provide reduced apertures 50 which' extend.

diagonally through the stem an d open into the chamber 16 intermediatethe upper and lower sets of cam surfaces. 7 7 I When the stem 40 ismoveddownwardly and rotated in the direction indicated'by the arrows inFigs. 4 and 5, the wings 47 engage the shoulders 36 of the cap and thecam surfaces 45'engage the tongues 34 of the upper reamer blocks 33 andthejcam surfaces .46 engage the-cam portions 36 of the center block 35thereby moving the reamers to an extended position as shown in Fig. 2,Uponcontinued rotationof the stem the wings 47 ro tate the body and capwith it. I

H When the stem is moved upwardly androtated in the oppositev directionthe stem cam surfaces 45 and 46 move out of engagement with the camportions 34 and 35 of the reamerswhereupon the cam portions 34 and 35may move inwardly untll theyengage the flat surfaces 44 of thestemasshown in Fig.6.

, ;In operation the hub 41 of the stem is secured to the sub of a stringof drilltubing, the body 12 is then rotated so that the cam portions34'and 36 may engage the flatsu'rfaces 44 ofthe stemjand then the deviceis lowered into the well. When the deviceis being lowered into the welland the stem is I rotatedto allow the retraction of' the reamersthe'weight of the body'and cap retains the wings 47 in the seats 25*.Thus the drill pipe i may be rotated when coupling additionalsectionsthereto withoutfrotatingthe stern rela tiveto thebody and cap,

- When the device reaches the bottom'of the well theweight ofthe bodyand cap .is carried by the formation whereupon when .it vis desired tooperate the device the stem 40 is moved downward so that the wings 47move out of the seats 25', the drill tubing is then rotated therebyrotating the stem 40 in the direction indicatedby.

the arrows in Figs. 4 and 5. As the stem is thus rotated the camsurfaces 45 and 46 move the reamers to an extended position as shown inFig. 2, and the wings 47 engage the cap shoulders 26 and are positionedin the seats 25 whereby upon continued rotation of the stem the body andcap will be rotated thereby causing the reamers to enlarge the well holeand the bit 14 to cut a new hole.

The circulating'fluid passes from the drill tubing intothe stem bores 48and 49 thence into the chamber 16 and through the recess 17 and theapertures 18 outadj acent each side of the bit. Some of the circulatingfluid passes through the stem apertures 50 by which it is directedtoward the upper reamer rolls 38 and thence out through the'apertures 20and some of the fluid passes from the chamber 17 through the apertures20around the lower reamer rolls 37. V

To withdraw the device 10 from the well the drill tubing is movedupwardly to disengagethe wings 47 from the seats 25 and is rotated in areverse direction, thereby rotating the stem 40 in a reverse directionwhereupon the reamer cams'urfaces may move inwardly intoengagement withthe flat surfaces 44 of the stem,thus' allowing thereamers to beretracted whenthey are drawn upwardly though the well casing. p

When the deviceis being drawn out of the hole the wings 47 arepositioned injthe' seats 25 thereby allowing the drill pipe to berotated to remove sections thereof without rotating the stem 40 relativeto the cap and body whereby the rotation of the stem does not actuatethe reamers to an extended position. From the foregoing description'itwill be apparent that we have'provided a novel boring tool which issimple in construction and highly eflicient inuse. y Havingthusfdescribed our invention, we

1. In a boring tool, -a casing, the lower end of said casing includinga'cuttinglbit, a plurality ofreamers pivoted on said casing, each ofsaidi'reamers including a cam engaging surface,'a bore in' said casing,aplurality of opposed recesses intermediate the-length of said bore, anupper seat recess adjacent one end 'of each of said' opposed recessesand a lower seat recess adjacent the opposite end of each of saidopposed recesses, a stem, said stem being positioned in said bore,a'plurality of opposed wings on said stem, said wings being positionedin said recesses and having restricted radial movement therein, saidstem including'a plurality of flat surfaces and a plurality of camsurfaces,'said cam surfaces beingadaptedin one position of said stem.

to engage saidcam engaging surfacesof said reamers to move said reamersoutwardly, said stem in another position being adapted to allow saidreamer cam surfaces to move inwardly into engagement with said flatsurfaces of said stem, said stem wings when said stem is rotated to movesaid reamers outwardly being adapted to engage a portion of said casingwhereby continued movementof said stem will rotate said casing, saidWings when said cam surfaces are in said first position being positionedin said lower seat recesses and said wings when said cam surfaces are insaid second position being positioned in said upper seat recesses.

2. In a boring tool, a body portion, the lower end of said bodyincluding a flat sided cutting bit, a plurality of blocks pivoted onsaid body portion, said blocks each having a socket recess in the upperface thereof, a plurality of shafts, the lower ends of said shafts beingpositioned is said sockets of said blocks, a plurality of upper blocks,the upper ends of said shafts beingpositioned in said upper blocks, achamber in said body, said upper blocks being positioned in said bodyand including cam engaging tongues positioned in said body chamber, acenter block positioned on said shafts intermediate the length thereof,said center blocks including cam engaging portions, a reamer rollerrotatably mounted on each of said shafts between said lower block andsaid center block and a reamer roller rotatably mounted on each of saidshafts between said upper block and said center block, a stem, said stembeing positioned in said body portion with the lower end of said stemextending into said body chamber, the lower portion of said stemincluding a plurality of fiat surfaces and an upper set of cam surfacesand a lower set of cam surfaces, said upper set of cam surfaces beingadapted in one position of said stem to engage said cam engagingportions of said center blocks and move said reamers outwardly, saidstem in another position being adapted to allow said reamer cam surfacesto move inwardly into engagement with said flat surfaces of said stem.

3. In a boring tool, a casing, the lower end of said casing including aflat sided cutting bit, said casing having a chamber and a recess at thebottom of said chamber, there being a plurality of aperturescommunicating with said recess and opening through said casing adjacentthe sides of said bit portion, a plurality of recesses in the outer faceof said 7 casing adjacent the lower end thereof, a

block positioned in each of said plurality of recesses, said blocksbeing pivotally secured to said casing, a socket recess in theupper faceof each of said blocks, a plurality of shafts, the lower ends of each ofsaid shafts being positioned in one of said socket recesses of saidblocks, a plurality of upper blocks, the upper ends of saidshafts beingpositioned in said upper blocks, said upper blocks being positioned insaid casing recesses and including cam engaging tongues positioned insaid chamber and extending above said recesses, a center blockpositioned on said shafts intermediate the length thereof, said centerblocks including cam engaging portions, a reamer roller rotatablymounted on each of said shafts between said lower block and said centerblock and a second reamer roller rotatably mounted on each of saidshafts between said upper block and said center block, there being abore in said casing and a pair of opposed circumferential recessesintermediate the length of said bore and longitudinal grooves in theinner face of said bore communicating with said circumferentialrecesses, a stem positioned in said bore with the lower end of said stemextending into said chamber, opposed wings on said stem,said wings beingpositioned in said circumferential recesses and having restricted radialmovement therein, the lower portion of said stem being reduced andincluding a plurality of upper flat surfaces and an upper set of camsurfaces and a plurality of lower fiat surfaces and a lower set of camsurfaces, said upper set of cam surfaces being adapted in one positionof said stem to engage said cam engaging portions of said upper blocksand said lower surfaces to engage said cam engaging portions of saidcenter blocks to move said reamers outwardly, said stem in anotherposition being adapted to allow said reamer cam surfaces to moveinwardly into engagement with said fiat surfaces of said stem, said stemwings when said stem is rotated to move said reamers outwardly beingadapted to engage a portion of said casing whereby continued movement ofsaid stem will rotate said casing.

4. In a boring tool, a body portion, a plurality of blocks pivoted onsaid body portion, said blocks each having a recess therein, a pluralityof shafts, the lower ends of said shafts being positioned in saidrecesses of said blocks, a plurality of upper blocks, the upper ends ofsaid shafts being positioned in said upper blocks, a chamber in saidbody, said upper blocks being positioned in said body and including camspositioned in said body chamber, a reamer roller rotatably mounted oneach of said shafts, a stem, said stem being positioned in said bodyportion and means on said stem to engage said cams to move said reamerrollers.

5. In a boring tool, a body portion, a plurality of blocks pivoted onsaid body portion, said blocks each having a socket therein, a pluralityof shafts, the lower ends of said shafts being positioned in saidsockets of said blocks, a plurality of upper blocks, the upper ends ofsaid shafts being positioned in said upper blocks, a chamber in saidbody,

said upper blocks beingpositione'd in' said body and including camsposition-ed in said body chamber, a center block positioned on each ofsaidshafts intermediate the length thereof, said center blocks includingcams,

' a reamer roller rotatably mounted on each of said shafts between saidlower blocks and said cams and move said reamer

